I never knew HC Robbins Landon, who has died at the age of 83. But like thousands of others around the world, he was the only classical music scholar I had ever heard of when I was growing up, thanks to the major books on Mozart he published with Thames and Hudson, the lavishly illustrated and infectiously enthusiastic Mozart: The Golden Years, and 1791: Mozart's Last Year. I was obsessed with Mozart and his music as a teenager, and Landon's books were my passport to the world of late 18th century Vienna, which he recreated with a detail and a flourish that I found irresistible, and inspired my own journey of discovery into Mozart's music. Even his name, with those extravagantly Americanised abbreviations, had an air of scholarly glamour about it – and sounds much better than Howard Chandler, his real moniker.

Barry Millington's obituary reveals how Landon achieved so much as a scholar who was able and willing to write for a mass audience. Almost uniquely in the field, Landon managed to break the often impermeable meniscus of obfuscation and academese that separates most musicologists from a wider public. Instead of insisting that he should be responsible for all of his work, Landon collaborated with fellow scholars and teams of editors and researchers.

That openness means that his books are much better, even today, than they might seem. Although some inside the academy were sniffy about his commercial success (and Landon did make serious money from the multiple editions and translations of his Mozart books), both The Golden Years and 1791 did some in-depth investigative work on Mozart's behalf. Just as the myth-building and hagiographising of the composer was reaching fever pitch for the 1991 celebrations of 200 years since his death, Landon's work revealed what really happened in his last year. 1791 scotched at a stroke the idiotic notion of Salieri's supposed poisoning of Wolfgang, and rehabilitated the reputation of Constanze, his widow, who we can now see as one of the most assiduous keepers of the compositional flame instead of as a lascivious harpy, the conventional view of her. Landon's 1791 was serious, forensic scholarship presented to the largest possible public, and it's still a model of how it should be done.

And Mozart wasn't even the centre of Landon's world – Haydn was the composer he really made his reputation with, in a five-volume life and works, the establishment of the Haydn Society, and countless articles and editions. But Landon could be wrong, most notoriously in believing that six newly discovered piano sonatas could only be by Haydn, when they were subsequently revealed as fakes written by a recorder player. He also gave his imprimatur to Herbert von Karajan's digital recordings of Haydn's London Symphonies, which made me – impressionable fool that I was – buy them, some of the dullest performances of these life-enhancing pieces ever made. But without HC Robbins Landon, all of our musical and Mozartian lives would be the poorer. At the end of The Golden Years, he writes that "In Masonic language, it was high midnight. One by one, all the lights of the temples were extinguished and darkness descended until 1918. The Mozartian era was at an end." The fact that the "Mozartian era" will now never end is no little thanks to Landon's work.